Many pets respond well to being given habitual places to sleep or otherwise rest, for which purpose a number of pet furniture elements have been developed. Most pet furniture, however, lacks flexibility of deployment. Climbing structures, cots and floor-cushions take up too much space in many rooms. They can also give the rooms a cluttered appearance. For some pets, notoriously including cats, that prefer to rest on high surfaces, beds at floor level will be abandoned for higher ground of the pet's choosing like the backs of sofas or the tops of book-cases. This can result in messes, broken objects knocked off of shelves, and other undesirable outcomes.